Been a while guys but I’ve got a problem I can’t figure out on my 700. Code reads Left Motor SOL no response. 523577.9 I’ve spent hours checking the wiring to the Solenoid and it’s all good. I’ve replaced the $1200 solenoid with absolutely no change. Ugh. Then a $600 speed sensor ugh ugh We’ve been running it this way for a couple months now, just can’t go faster than 1.5. Which is getting pretty old. Have checked the voltages coming right out of the TCU for both the right and left side solenoids. Right side starts at 0.00 and then goes to 27 until the TCU realizes the left drive motor isn’t speeding up and then it drops the voltage. Left side starts at 1.03 and doesn’t change for anything. So the question is, is there certain data that the TCU requires to ramp up the voltage to the solenoid? Could I have a cut wire on something not related but that’s why the tcu won’t send the voltage? Or rather is this just a pure sign of a bad tcu? I took the tcu to an old computer geek and he replaced the 2 capacitors with no change. He said he could check a lot more if he had the wiring diagram to that TCU. Does anyone have one?
Need the machine serial number please. Not available. Were they load tested?
1T0700jxafd277022 Dang No, just tested with a meter. But Also have switched the connectors on the left and right solenoids and the code doesn’t switch over. Which I’m inclined to think that rules out solenoids and hardware within the drivemotors. But I guess that wouldn’t rule out the wiring.
Correct in that it does not rule out the wiring. So, either the wiring is faulty or the TCU has a bad driver.
Ok. But. If I unhook the wires on the right side solenoid, and then check the voltage coming out of the tcu it still sends out the voltage the same as it does with them hook up. So my reasoning was that if the left side had a bad wire the tcu would still be sending out the voltage. But it’s not, see I’m checking the voltage right at the tcu, about and inch down from the connection. Would you say I’m right?
Terminals in the TCU connector are loose/corroded? If not, then you may be TCU bound...
Good clean, tight Ugh that’s like nearly the last thing I want to hear.
Any update?
Sorry, just seen this. Nope, still been using as is. But was going to try to get the tcu sent off this next week somewhere for repair
I recently just had a similar issue on a 700L Right Motor Solenoid Circuit Fault I narrowed it down to a harness that actually fried that single circuit on the board for us. If you trace the wires going back to the ECU the hot side of that harness (2 wires) should give out about 5v with power on. We were getting 5v to one side solenoid track but not 5v to the other side. I never saw any ramping for us. The other issue we had is that our harness was chaffed in several. SEVERAL spots. I was able to replace several sections without having to remove the cab and replace the harness. What I actually ended up doing was getting some more of those connector plugs and remaking an “overlay” harness. That tapped into the tcu computer right at the back of the plug. And right into the solenoids directly. Because according to the wiring diagram for a 700L it’s straight with nothing between. What I found out is that yes, a harness chaffed out in sections will actually make your multimeter go “beep” with continuity. But having one little bitty copper wire instead of the 2-3 dozen it’s supposed to have. Won’t carry the load that circuit needs. So it must have ended up frying that section. Or grounding out or something. A new TCU for our machine wasn’t really that bad. About $1500 I’d say. And then a new harness on top that I made. Ended up solving our Right Motor Solenoid Circuit Fault. Which was causing us to not go past 1.5 either. Hope this helps you. Or maybe someone else reading on here